Caroline Wozniacki is set to retire after the Australian Open, scene of the Dane's only Grand Slam triumph.
AFP Sport picks out five memorable moments on and off the court in the former world number one's career:
- World number one -
Wozniacki hit the summit of the world rankings in October 2010 and finished the year in top spot. She repeated the feat in 2011 and would spend 67 weeks as number one. However, because the wait for a first Grand Slam title dragged on, the ranking weighed heavily. For a while she was an unwelcome member of the unofficial 'Slamless Wonders' club -- number one female players never to win a Major.
- Slam at last -
Wozniacki's wait for a maiden Grand Slam went on and on. She lost to close friend Serena Williams in the final of the US Open in 2014, having similarly been beaten in the 2009 final at Flushing Meadows by Kim Clijsters. Wozniacki's debut Major triumph finally arrived in 2018 at the Australian Open, where she defeated Simona Halep in the final. She would top the rankings once again that same year.
- Serena Williams bond -
Wozniacki and Williams form one of the best-known friendships in tennis and they played as doubles partners this month in Auckland, where they reached the final. The two are so close that the American was a bridesmaid at Wozniacki's wedding last year to former NBA star David Lee. Speaking together to Vogue in 2015, Wozniacki remembered how supportive Williams was when golfer Rory McIlroy broke off his engagement with the Dane. "She was really there for me when I needed her the most and that's why I think our friendship is so strong now," said Wozniacki.
- McIlroy engagement, then split -
He was one of the best golfers in the world; she was one of the best women's tennis players. Wozniacki and Northern Ireland's McIlroy appeared to have it all and were engaged to be married. The wedding invites had just gone out. But suddenly, in a brief phone call in 2014, McIlroy ended the most famous relationship in sport. Wozniacki later said that she was "thankful" and joked that at least she could go back to wearing high heels, after ditching them to avoid towering over the 5ft 9ins (175cm) golfer.
- Arthritis shock -
In October 2018 Wozniacki shocked the tennis world by revealing that she had been diagnosed with rheumatoid arthritis, an autoimmune disease that causes swelling of the joints and fatigue. She said that she had not been feeling well for some time and had woken up one morning not being able to lift her arms over her head. But Wozniacki denies that her retirement is because of her condition.